Now to the latest in the Oscar Pistorius trial. The prosecution is wrapping up its case, calling its final witness this is morning. ABC's Matt dputmgutman is at the courthouse. Reporter: Good morning, josh. This is probably the most damning testimony we have heard this morning so far. One woman said she heard a woman scream two football feemds away. The screams so startling, she turned to her husband and said, this must be a family murder. In a trial so much about sound, we could only hear the testimony of Oscar Pistorius' neighbor. It sounded to me as if the screaming was coming closer. Reporter: What she said she heard was a house of horror. Could you hear the screaming? Up until the first or second set of shots. Reporter: She's one of the final prosecution witnesses. They allege that Pistorius, and his girlfriend, the mold reeva steenkamp, had an explosive argument on Valentine's day when that would only end when he gun her down. I also could hear a man screaming. I could not make out words. After the second set of shots, it became quiet. I heard no more screaming, either male or female. Reporter: There were no eyewitnesses that night. Only so called ear witnesses like this one who could see his house from her bedroom, but not inside. The judge asked her to slow it down. You have to slow down a little bit. Reporter: Pistorius pleaded not guilty, saying he mistook his blond reality star girlfriend for an intruder and that I was he who screamed that night when he realized his mace take. The defense questioned her memory. You had been in a sleep and then you woke up? Reporter: Growing con ten insurance tious. She refused to budge about what she heard. I'm 100% absolutely convinced it was a female. Reporter: Now this is key because now we have multiple witnesses saying they heard a woman scream that night, contradicting Pistorius' account. Tomorrow, we expect a cell phone expert to take the stand. Reeva steenkamp had two cell phones on her -- All right? Matt? Thank you very much.

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